relay: Limit Directory Authority Addresses to Address and ORPort

Closes #33239

Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit is contained in:
David Goulet 2020-07-22 14:17:21 -04:00
parent a4c5b7d742
commit f0da04bb7b

View File

@ -14,6 +14,7 @@
#include "core/mainloop/mainloop.h" #include "core/mainloop/mainloop.h"
#include "feature/control/control_events.h" #include "feature/control/control_events.h"
#include "feature/dirauth/authmode.h"
#include "lib/encoding/confline.h" #include "lib/encoding/confline.h"
#include "lib/net/gethostname.h" #include "lib/net/gethostname.h"
@ -536,12 +537,15 @@ resolved_addr_set_last(const tor_addr_t *addr, const char *method_used,
*done_one_resolve = true; *done_one_resolve = true;
} }
/** Ease our lives. Typedef to the address discovery function signature. */
typedef fn_address_ret_t
(*fn_address_t)(
const or_options_t *options, int warn_severity, int family,
const char **method_out, char **hostname_out, tor_addr_t *addr_out);
/** Address discovery function table. The order matters as in the first one is /** Address discovery function table. The order matters as in the first one is
* executed first and so on. */ * executed first and so on. */
static fn_address_ret_t static const fn_address_t fn_address_table[] =
(*fn_address_table[])(
const or_options_t *options, int warn_severity, int family,
const char **method_out, char **hostname_out, tor_addr_t *addr_out) =
{ {
/* These functions are in order for our find address algorithm. */ /* These functions are in order for our find address algorithm. */
get_address_from_config, get_address_from_config,
@ -550,7 +554,23 @@ static fn_address_ret_t
get_address_from_hostname, get_address_from_hostname,
}; };
/** Length of address table as in how many functions. */ /** Length of address table as in how many functions. */
static const size_t fn_address_table_len = ARRAY_LENGTH(fn_address_table); static const size_t fn_address_table_len =
ARRAY_LENGTH(fn_address_table);
/* Address discover function table for authorities (bridge or directory).
*
* They only discover their address from either the configuration file or the
* ORPort. They do not query the interface nor do any DNS resolution for
* security reasons. */
static const fn_address_t fn_address_table_auth[] =
{
/* These functions are in order for our find address algorithm. */
get_address_from_config,
get_address_from_orport,
};
/** Length of address table as in how many functions. */
static const size_t fn_address_table_auth_len =
ARRAY_LENGTH(fn_address_table_auth);
/** @brief Attempt to find our IP address that can be used as our external /** @brief Attempt to find our IP address that can be used as our external
* reachable address. * reachable address.
@ -624,6 +644,8 @@ find_my_address(const or_options_t *options, int family, int warn_severity,
const char *method_used = NULL; const char *method_used = NULL;
char *hostname_used = NULL; char *hostname_used = NULL;
tor_addr_t my_addr; tor_addr_t my_addr;
const fn_address_t *table = fn_address_table;
size_t table_len = fn_address_table_len;
tor_assert(options); tor_assert(options);
tor_assert(addr_out); tor_assert(addr_out);
@ -639,15 +661,20 @@ find_my_address(const or_options_t *options, int family, int warn_severity,
return false; return false;
} }
/* For authorities (bridge and directory), we use a different table. */
if (authdir_mode(options)) {
table = fn_address_table_auth;
table_len = fn_address_table_auth_len;
}
/* /*
* Step 1: Discover address by attempting 3 different methods consecutively. * Step 1: Discover address by calling methods from the function table.
*/ */
/* Go over the function table. They are in order. */ /* Go over the function table. They are in order. */
for (size_t idx = 0; idx < fn_address_table_len; idx++) { for (size_t idx = 0; idx < table_len; idx++) {
fn_address_ret_t ret = fn_address_table[idx](options, warn_severity, fn_address_ret_t ret = table[idx](options, warn_severity, family,
family, &method_used, &method_used, &hostname_used, &my_addr);
&hostname_used, &my_addr);
if (ret == FN_RET_BAIL) { if (ret == FN_RET_BAIL) {
return false; return false;
} else if (ret == FN_RET_OK) { } else if (ret == FN_RET_OK) {